Flabelligena amoureuxi new genus, new species (Polychaeta: Acrocirridae) from Crozet Islands (Indian Ocean)

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BULLETIN OF MARINE SCIENCE, 68(1): 125–131, 2001 NEW TAXA PAPER
FLABELLIGENA AMOUREUXI NEW GENUS, NEW SPECIES
(POLYCHAETA: ACROCIRRIDAE) FROM CROZET ISLANDS
(INDIAN OCEAN)
Patrick Gillet
ABSTRACT
A new species of Annelida: Polychaeta, Flabelligena amoureuxi, family Acrocirridae
Banse is described from the Crozet Islands (Indian Ocean). Specimens were collected
during the Oceanographic Expedition Marion Dufesne MD/08 BENTHOS in 1974.
Flabelligena amoureuxi is compared with the other species of the genus Flabelligena
and the genus Flabelligera Hartman, 1965.
After the Marion Dufresne MD/03 BIOMASS Cruise in 1974, a new expedition was
undertaken to study the benthic invertebrates from the South West Indian Ocean. Poly-
chaetes collected during the MD/08 BENTHOS Expedition from Marion, Prince Edward
and the Crozet Islands were studied by Gillet (1991). A new maldanid, Axiothella
crozetensis, was described (Gillet, 1989).
MATERIALS AND METHODS
A description of the sampling sites of the MD/08 BENTHOS Expedition was provided by Arnaud
and Hureau (1979). Different sampling methods were used: Charcot dredge, Okean grab, Lithods
nets and trawl. Specimens were conserved in 70% ethanol and observed with light microscopy with
an Olympus CHT2 and with a scanning electron microscopy on an Olympus JSM 5200 using the
critical point as a drying method.
Material was deposited in the Institut de Recherche Fondamentale et Appliquée, Angers-France
with the registration number IRFA ACR001, IRFA ACR003 and IRFA ACR004. A duplicate collec-
tion was deposited in the Museum National d’Histoire Naturelle de Paris, France and in the South
African Museum, Cape Town, South Africa.
Family Acrocirridae Banse, 1969
The acrocirrids are Polychaeta sedentaria with frontal palps, a reduced prostomium
and generally with eyes. The family Acrocirridae is a small family with three genera:
Acrocirrus Grube, 1872, Flabelligella Hartman, 1965 and Macrochaeta Grube, 1850.
The type genus is Acrocirrus Grube, 1872 it has was chosen because the specimens are
usually large enough to allow recognition of all diagnostic characters of the family. The
genus Acrocirrus Grube, 1872 and Macrochaeta Grube, 1850 were removed from the
Cirratulidae and placed in the family Acrocirridae by Banse (1969). The scalibregmid
body with papillae remains flabelligerids but the pair of cirriform appendages and com-
posite neurochaetae are closely related to cirratulids.
Genus Flabelligella Hartman, 1965
Type species Flabelligella papillata Hartman, 1965: 177, plate 38.
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Figure 1. Flabelligena amoureuxi n. sp. (Holotype IRFA ACR 001). A, anterior region; B, papilla;
C, notochaeta ; D, neurochaeta.
The genus Flabelligella has a rounded prostomium without a cephalic cage. Neuropo-
dia have composite falcigerous chaetae and notopodia have simple and cross-barred or
spinulose chaetae.
The genus Flabelligella Hartman, 1965 was placed in the family Flabelligeridae in
relation to the composite neurochaetae as in Flabelligera, but without a cephalic cage as
in Brada. Hartman (1971) transferred the genus to the family Fauveliopsidae Hartman,
1971; then Orensanz (1974) to the family Acrocirridae Banse, 1969.
GILLET: FLABELLIGENA AMOUREUXI, NEW GENUS, NEW SPECIES 127
A C
B D
Figure 2. Scanning Electron Micrographies of Flabelligena amoureuxi n. sp.: (Paratype) A, anterior
region ×100; B, neurochaetae; C, neurochaetae ×1000; D, details of neurochaetae ×7800.
Flabelligena new genus
Type species Flabelligena cirrata (Hartman and Fauchald, 1971) plate 18, Figs. a–c.
The presence of a pair of palps, first found in the species F. cirrata Hartman and Fauchald,
1971 is a cirratulid character which is unknown for any other flabelligerids. These speci-
mens have also spinulose or serrated notochaetae instead of cross-barred notochaetae. In
relation to the presence of a pair of palps and to the absence of cross-barred chaetae, the
suggestion is to separate the Flabelligella species into two different genera: the genus
Flabelligella with the type species Flabelligella papillata Hartman, 1965 and the genus
Flabelligena with the type species F. cirrata (Hartman and Fauchald, 1971).
Flabelligena amoureuxi new species
(Figs. 1 A–D; 2 A–D; 3; Table 1)
Material Examined.—Holotype: The Crozet Islands 17.04.1976 sta. 60, sampling BB
250, 46°03.4S; 49°47.6E; 27 chaetigers, 7 mm long, 0.5 mm wide. Paratypes: The Crozet
128 BULLETIN OF MARINE SCIENCE, VOL. 68, NO. 1, 2001
Figure 3. A comparison of types of chaetae in the species of the genus Flabelligella Hartman, 1965
and the genus Flabelligena gen. nov. A, F. amoureuxi n. sp.; B, F. cirrata Hartman and Fauchald; C,
F. erratica Orensanz; D, F. minuta Hartman; E, F. mexicana Fauchald and F. papillata Hartman.
Islands sta. 59 (BB 253) 45°59.8S, 49°58.3E, 2 examples; sta. 60 (BB 250) 46°03.4S,
49°47.6E, 6 examples; sta. 64 (BB 264) 46°02.0S, 49°08.5E, 6 examples. Material de-
posited at IRFA Museum IRFA Holotype: ACR 001 Paratypes: ACR 003 and ACR 004.
Description.—The type has 27 chaetigers, it is 7 mm long and 0.5 mm wide.
The prostomium, eyeless, is smooth and rounded, dark brown at the tip. The peristomium
is a smooth ring with a pair of long palps, reaching sometimes the third chaetiger. The
cephalic cage is missing (Figs. 1A,2A).
GILLET: FLABELLIGENA AMOUREUXI, NEW GENUS, NEW SPECIES 129
Table1.AcomparisonofsomecharactersinexistingspeciesofthegenusFlabelligellaHartman,1965.
Species Typelocality Palpi Chaetigers Notochaetae Neurochaetae Eyes
depth
F.mexicana Cedros 0 9 cross-barred2 composite7−8 0
Fauchald Island
(1972) abyssal
F.minuta NewEngland 0 10 cross-barred1−3 composite4−8 0
Hartman 400−4825m
(1965)
F.papillata Bermuda 0 20 cross-barred? composite1−2 0
Hartman 770−4825m
(1965)
The body, white in ethanol is covered with epithelial papillae. Epithelial papillae are
cylindrical and covered with mud and sand particles. The tip is enlarged (Fig. 1B).
The first four chaetigerous segments are shorter than the following. The next five
chaetigers are longer and enlarged. Posterior segments are slenderer and cylindrical. Seg-
mental lines are not visible. Parapodia are reduced without acicula. Simple slender
notochaetae are capillary spinulose (Fig. 1C). Neurochaetae are large composite spinigers
with a hinged distal end (Figs. 1D,2B,C,D). There are four composite neurochaetae on
each side from the first to the fourth chaetigers. The number of the chaetae varies in some
chaetigers between 3 to 5 with a single simple notochaetae but no chaetal variations along
the body. The posterior end has no modified structure. The pygidium is unknown.
Discussion.—F. amoureuxi differs from F. mexicana Fauchald (1971), F. minuta Hartman
(1965) and F. papillata (Hartman, 1965) by the presence of a pair of palps and by the
presence of spinulose notochaetae instead of cross-barred notochaetae. It differs also from
F. erratica Orensanz (1974) by the absence of eyes and a prostomium which is rounded
instead of pentagonal. Neurochaetae are not curved and serrated papillae are long and
dense and not small and widely spaced as in F. cirrata Hartman and Fauchald (1971). It
has only one simple notochaeta and generally 4 composite neurochaetae instead of 4 to 8.
In relation to morphology and ecology, this is the first species collected from Subantarc-
tic Islands. Amoureux (1982) found some specimens of F. papillata collected during the
Thalassa Cruise in the North Atlantic Ocean at a depth from 400 to 2000 m. F. papillata
was also found along the Chile coast (Hartman, 1967) at a depth from 115 to 4099 m
(Tables 1,2).
Table2.AcomparisonofsomecharactersinexistingspeciesofthegenusFlabelligenagen.nov.
Species Typelocality Palpi Chaetigers Notochaetae Neurochaetae Eyes
depth
F.amoureuxi Crozet 2 30 spinulose1 composite3−5 0
n.sp. 215−980m
F.cirrata NewEngland 2 17−24 serrated1−2 composite4−8 0
Hartman& 466−530m
Fauchald(1971)
F.erratica Argentina 2 20−30 spinulose1 composite1−3 2
Orensanz(1974) 288m
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Habitat.—F. amoureuxi lives at depths from 215 to 980 m on clay or clay-sand around
the Crozet Islands associated with Paraonis uncinatus.
Etymology.—F. amoureuxi is named after Dr. Louis Amoureux, in appreciation of his
research on polychaetes. He was a taxonomist at the Université Catholique de l’Ouest,
Angers, France.
KEY OF THE GENERA FLABELLIGELLA AND FLABELLIGENA
1a. A pair of palps present, Spinulose notochaetae........................................... genus Flabelligena
1b. Palps absent, cross-barred notochaetae .......................................................genus Flabelligella
GENUS FLABELLIGENA
1a. One or two serrated notochaetae.................................................................................. F. cirrata
1b. No serrated notochaetae, but one spinulose .............................................................................2
2a. A pair of eyes, prostomium pentagonal, 1–3 composite falciger neurochaetae .........F. erratica
2b. Eyes absents, prostomium rounded, 3–5 composite falciger neurochaetae........... F. amoureuxi
GENUS FLABELLIGELLA
1a. More than 20 chaetigerous segments........................................................................F. papillata
1b. Up to 10 chaetigerous segments...............................................................................................2
2a. Ten chaetigerous segments, 2 cross-barred notochaetae and 7-8 composite falciger neurochaetae
.................................................................................................................................F. mexicana
2b. Nine chaetigerous segments, 1–3 cross-barred notochaetae and 4–8 composite falciger
neurochaetae................................................................................................................F. minuta
ACKNOWLEDGMENTS
I would like to thank the Comité National Français des Recherches Antarctiques (T.A.A.F.), P.
Arnaud, Station Marine d’Endoume, Marseille and M. Segonzac, Centob IFREMER, Brest. This
study could not have been carried out without the loans of specimens by Dr. Renaud-Mornant,
Museum National d’Histoire Naturelle de Paris, France and by the South African Museum, Cape
Town South Africa.
LITERATURE CITED
Amoureux, L. 1982. Annélides polychètes recueillies sur la pente continentale de la Bretagne à
l’Irlande, Campagne de la “Thalassa” (suite et fin) avec la description de quatre espèces nouvelles
pour la science: II Inventaire taxonomique annoté de toutes les Polychètes Sédentaires. Cah.
Biol. Mar. XXIII: 179–214.
Arnaud, P. M. and J. C. Hureau. 1979. Compte-rendu de la campagne MD/08 BENTHOS (7 mars–
26 avril 1976). Comité National Français des Recherches Antarctiques 44: 1–38.
Banse, K. 1969. Acrocirridae n. fam. (Polychaeta sedentaria). J. Can. Res. Fish. Bd. 26(10): 2595–
2620.
Fauchald, K. 1972. Benthic polychaetous annelids from deep water off western Mexico and adja-
cent areas in the Eastern Pacific Ocean. Allan Hancock Monogr. Mar. Biol. 7: 1–575.
Gillet, P. 1989. Axiothella crozetensis, a new species of maldanid polychaete from Crozet Islands
(Indian Ocean). Proc. Biol. Soc. Wash. 102(4): 866–871.
GILLET: FLABELLIGENA AMOUREUXI, NEW GENUS, NEW SPECIES 131
_______. 1991. Biogeography and polychaete assemblages from Subantarctic Islands (Indian Ocean).
Marion Dufresne MD/08 BENTHOS Expedition to Marion, Prince Edward and Crozet Islands.
Bull. Mar. Sci. 48: 358–368.
Grube, A. E. 1850. Die familien der Anniden. Arch.Naturgesch 16(1): 249–364
__________. 1872. Die Familie des Cirratulidien. Sitzunsber. der Schlesichen Gesellschaft.: 59–
68.
Hartman O. 1965. Deep-water benthic polychaetous annelids off New England to Bermuda and
other North Atlantic Areas. Allan Hancock Fdtn. Publ. 28: 1–378.
_________. 1967. Polychaetous annelids collected by the USNS ELTANIN and STATEN ISLAND cruises,
chiefly from Antarctic Seas. Allan Hancock Monogr. Mar. Biol. 2. 337 p.
_________. 1971. Abyssal polychaetous annelids from the Mozambique Bassin off southwest Af-
rica with a compendium of abyssal polychaetous annelids from world-wide Areas. J. Fish Res.
Pod. 28(10): 1407–1428.
_________ and K. Fauchald. 1971. Deep-water nenthic polychaetous annelids of New England to
Bermuda and other north Atlantic areas. Part II. Allan Hancock Monogr. Mar. Biol. 6: 1–327.
Orensanz, J. M. 1974.- Policheto de la Provincia biogeographica Argentina X. Acrocirridae
Neotropica 20(63): 113–118.
Rozbaczylo, N. 1985. Los Anélidos Poliquetos de Chile. Indice Sinonimico y distribucion
geographica de especies. Monograficas Biologicas: 284 p.
DATE SUBMITTED: November 10, 1998. DATE ACCEPTED: November 6, 2000.
ADDRESS: Département des Sciences de la Vie et de la Terre - Institut d’Ecologie Appliquée, U.C.O.
3 place André Leroy B.P.808 49008 Angers Cedex 01 France.